In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound casting.The effects of composite trea...In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound casting.The effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were studied.Results demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg bimetal.The HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the interface.The Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic structures.The interface resulting from the composite treatment has a lower hardness than that without treatment.The acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg side.The fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite treatment.The shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.展开更多
A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of th...A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of the PEO-based electrolytes.Experimental and molecular dynamics simulation results indicated that the electrolyte with 10 wt.%CAB(PL-CAB-10%)exhibits high ionic conductivity(8.42×10~(-4)S/cm at 60℃),high Li+transference number(0.46),wide electrochemical window(4.91 V),good thermal stability,and outstanding mechanical properties.Furthermore,PL-CAB-10%exhibits excellent cycle stability in both Li-Li symmetric battery and Li/PL-CAB-10%/LiFePO4 asymmetric battery setups.These enhanced performances are primarily attributable to the introduction of the versatile CAB.The abundant metal sites in CAB can react with TFSI~-and PEO through Lewis acid-base interactions,promoting LiTFSI dissociation and improving ionic conductivity.Additionally,regular pores in CAB provide uniformly distributed sites for cation plating during cycling.展开更多
A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fractu...A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fracture surface of Al/Cu joints were studied by scanning electron microscopy（SEM） and X-ray diffraction（XRD）.The mechanical properties of the Al/Cu bimetals were measured by tensile shear and microhardness tests.The results show that the Ni interiayer can effectively eliminate the formation of Al-Cu intermetallic compounds.The Al/Ni interface consists of the Al3Ni and Al3Ni2 phases,while it is Ni-Cu solid solution at the Ni/Cu interce.The tensile shear strength of the joints is improved by the addition of Ni interiayer.The joint with Ni interiayer annealed at 500 ℃ exhibits a maximum value of tensile shear strength of 34.7 MPa.展开更多
基金funded by the National Natural Science Foundation of China(Nos.52271102,52075198 and 52205359)。
文摘In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound casting.The effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were studied.Results demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg bimetal.The HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the interface.The Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic structures.The interface resulting from the composite treatment has a lower hardness than that without treatment.The acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg side.The fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite treatment.The shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.
基金supported by the National Natural Science Foundation of China(No.21501015)the Hunan Provincial Natural Science Foundation,China(No.2022JJ30604)Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation,China(No.2022CL01)。
文摘A composite solid electrolyte comprising a Cu-Al bimetallic metal-organic framework(CAB),lithium salt(LiTFSI)and polyethylene oxide(PEO)was fabricated through molecular grafting to enhance the ionic conductivity of the PEO-based electrolytes.Experimental and molecular dynamics simulation results indicated that the electrolyte with 10 wt.%CAB(PL-CAB-10%)exhibits high ionic conductivity(8.42×10~(-4)S/cm at 60℃),high Li+transference number(0.46),wide electrochemical window(4.91 V),good thermal stability,and outstanding mechanical properties.Furthermore,PL-CAB-10%exhibits excellent cycle stability in both Li-Li symmetric battery and Li/PL-CAB-10%/LiFePO4 asymmetric battery setups.These enhanced performances are primarily attributable to the introduction of the versatile CAB.The abundant metal sites in CAB can react with TFSI~-and PEO through Lewis acid-base interactions,promoting LiTFSI dissociation and improving ionic conductivity.Additionally,regular pores in CAB provide uniformly distributed sites for cation plating during cycling.
基金financially supported by the National Key Research and Development Program of China(No.2020YFB0311201)the National Natural Science Foundation of China(No.51627802)。
基金support from the National Science Foundation of China (No.51971249)the Natural Science Foundation of Shandong Province,China (No.ZR2020KE012)the Science and Technology Planning Project of Longkou City,China (No.2021KJJH025).
基金Projects (51274054,51375070,51271042) supported by the National Natural Science Foundation of ChinaProjects (2013M530913) supported by the China Postdoctoral Science Foundation
文摘A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fracture surface of Al/Cu joints were studied by scanning electron microscopy（SEM） and X-ray diffraction（XRD）.The mechanical properties of the Al/Cu bimetals were measured by tensile shear and microhardness tests.The results show that the Ni interiayer can effectively eliminate the formation of Al-Cu intermetallic compounds.The Al/Ni interface consists of the Al3Ni and Al3Ni2 phases,while it is Ni-Cu solid solution at the Ni/Cu interce.The tensile shear strength of the joints is improved by the addition of Ni interiayer.The joint with Ni interiayer annealed at 500 ℃ exhibits a maximum value of tensile shear strength of 34.7 MPa.
